The Application Of Polyurethane Injecting Method In The Asphalt Pavement Structure And The Anlysis Of The Motion Response Of This Application

Recently, good results have been achieved by using Polyurethane Injecting Method in the maintenance of highways at home and abroad, and some research has been done about the dynamical analogue of FWD and the dynamic response analysis of asphalt pavement structure under dynamic load, but there is few research about the dynamic response and the evaluation of the project effect of the pavement structure after injection. This paper introduces the Polyurethane Injecting Method and the physical and mechanical properties of polymeric materials at first, analyses the dynamic response of asphalt pavement structure after injection under 2-D and 3-D finite element model by choosing appropriate polymeric materials computation module, evaluates the effects of the dynamic response of asphalt pavement structure after injection by using two nondestructive detection techniques of FWD deflection detection and the ground penetrating radar in the end. Follows are the main contents of this paper:(1)This paper generalizes common faults of the asphalt pavement structure and traditional maintenance methods, and points out defects of traditional maintenance methods. By introducing properties of polymeric materials and the strengthening principle, steps of polyurethane injection and technologies of the Polyurethane Injecting Method, this paper analyzes the advantages of the Polyurethane Injecting Method in the maintenance of the asphalt pavement at home and abroad.(2)By analyzing results of the polymeric materials indoor mechanical tests, this paper chooses appropriate models and analysis parameters preparing for building ANSYS analysis models.(3)This paper introduces detailedly the primary theory of the numerical analysis of the pavement structure dynamic response and the principle of the FWD, and analyzes the dynamic response of the asphalt pavement structure under dynamic FWD loads before injection by using ANSYS, providing comparison for the dynamic response of the asphalt pavement structure after injection.(4)This paper analyzes the dynamic response of the asphalt pavement structure under dynamic FWD loads after injection by using ANSYS, and calculates the deflection of the load center point and stress of every direction on the top of the polyurethane layer with different moduluses and thickness of the surface layer, moduluses of the roadbed.(5)By introducing the principle of the FWD and the ground penetrating radar, this paper compares the results of the asphalt pavement structures before and after injection, and proves the feasibility of the evaluation of the injection effects of the two nondestructive detection techniques towards asphalt pavement structures.